SANTA CLARA, Calif. — If the San Francisco 49ers are going to rebound from their tough final-seconds defeat in Minnesota, they’re going to have to do it without running back Frank Gore.

Gore will miss at least three weeks after MRI results revealed Monday that he suffered a right-ankle strain and a right-foot sprain on the team’s first play from scrimmage Sunday against the Vikings. The 49ers announced Gore’s status via an e-mail sent Monday night and did not make any team officials available for comment.
Earlier Monday, coach Mike Singletary said at his weekly news conference that the injury was unrelated to the ankle sprain Gore suffered against Seattle on Sept. 20 and noted, “It is not believed to be serious.”
If the three-week prognosis holds true, Gore will miss two games. The 49ers play host to St. Louis and Atlanta the next two weeks before a bye on Oct. 18. They play at Houston on Oct. 25.
Without Gore, who rushed for 207 yards against the Seahawks and came into last weekend as the NFC’s second-leading rusher, the 49ers will rely on rookie Glen Coffee, who carried 25 times for 54 yards (2.2 average) against Minnesota.
The setback was the latest in a series of ankle problems Gore has experienced the past three seasons. Gore missed two games late last season because of an ankle injury and was also troubled throughout much of 2007 with a nagging ankle problem that caused him to miss two games and severely diminished his production.
The news about Gore comes on the heels of a heartbreaking 27-24 loss to the Vikings. Singletary had a pointed message Monday about dwelling on the loss: Get over it, and quickly.
From the coach’s view, speculating on what might have been done differently not only is dumb but also dangerous.
“I think you take it and be man enough to take it,” he said. “You chew it, you spit it out, you learn from it, and you get ready for the next game. I think winners let it go, winners move forward. I think losers just sit there and wallow, talk about it all week. And it screws you up for the next opportunity going forward.”
With the 0-3 St. Louis Rams coming to Candlestick Park on Sunday, Singletary is mindful of a mental hangover. As much as not being able to put the loss to the Vikings in the past, he believes not being mentally prepared for the Rams would reflect poorly on the week-to-week ideology he is trying to implement.
“One of the big things we’re always talking about is respect,” he said. “We’re not good enough to look at St. Louis or any other team and say, ’Wow, we’re going to have a hard time getting ready for these guys.’ We have a goal, a destination we’re trying to get to. It’s about us, not about them. We have to stay focused on the goal at hand, and if we don’t stay focused, then we’re not who we say we are.”
-- Singletary did address the two primary talking points in the wake of the defeat — calling three straight running plays when they needed just one first down to run out the clock, and then playing what appeared to be a prevent defense on the Vikings’ final drive.
With a 24-20 lead and 1:49 to go, offensive coordinator Jimmy Raye elected to call three straight runs, including on third-and-six (Coffee got 2 yards). The Vikings called a timeout after each play and got the ball back on a punt at their own 20 with 1:29 left.
“It is very easy to sit there, look at the game and say, ’Why didn’t you do this? Why didn’t you do that?’ “ Singletary said. “The bottom line is (Raye) called the things that he called because it made sense. Obviously, every decision that you make, when it doesn’t work, then all of a sudden it doesn’t make sense. Just understand that you call plays because you believe they’ll work.”
As for the defensive strategy on the last drive, Singletary flatly declared that the 49ers were not in a prevent.
“We were in a defense where we were going after the quarterback,” he said. “We did not get the quarterback down, (Brett Favre) threw the ball, they made plays.”
—Two other 49ers, tackle Joe Staley and safety Reggie Smith, had MRIs on Monday. Staley has a right-quad contusion and is listed as day-to-day. Smith has a right-groin strain and will be re-evaluated in two weeks.